Preventing Osteoporosis
Osteoporosis, or porous bone, is a disorder in which bones become increasingly porous or brittle, subject to fracture. Men as well as women are affected by osteoporosis, a disease that can be prevented and treated. According to the National Institute of Health, osteoporosis is a major public health threat for 44 million Americans, 68 percent of whom are women. Based on figures from hospitals and nursing homes, the estimated national direct expenditures for osteoporosis and related fractures total $14 billion each year.
What Is Bone?
Bone is living, growing tissue. It is made mostly of collagen, a protein that provides a soft framework, and calcium phosphate, a mineral that adds strength and hardens the framework.
Throughout your lifetime, old bone is removed (resorption) and new bone is added to the skeleton (formation). During childhood and teenage years, new bone is added faster than old bone is removed. As a result, bones become larger, heavier, and denser. Bone formation outpaces resorption until peak bone mass (maximum bone density and strength) is reached around age 30. After that time, bone resorption slowly begins to exceed bone formation.
For women, the most bone loss occurs in the first few years after menopause, and it continues into the postmenopausal years. Osteoporosis – which mainly affects women but may also affect men – will develop when bone resorption occurs too quickly or when replacement occurs too slowly. Osteoporosis is more likely to develop if you did not reach optimal peak bone mass during your bone-building years.
Prevention & Treatment
To reach optimal peak bone mass and continue building new bone tissue as you age, there are several factors you should consider.
Calcium: An inadequate supply of calcium over a lifetime contributes to the development of osteoporosis.
Vitamin D: Vitamin D plays an important role in calcium absorption and in bone health. It is made in the skin through exposure to sunlight. While many people are able to obtain enough vitamin D naturally, studies show that vitamin D production decreases in the elderly, in people who are housebound, and for people in general during the winter.
Exercise: Like muscle, bone is living tissue that responds to exercise by becoming stronger. Weight-bearing exercise is the best for your bones because it forces you to work against gravity. Examples include walking, hiking, jogging, stair climbing, weight training, tennis, and dancing.
Importance of Physical Activity
Bone adapts to strain by increasing or decreasing its mass and density. When strains (non-injury) are higher than usual, bone formation exceeds resorption and bone mass and bone strength are increased. There is a relationship between the volume of exercise and increased bone mineral density. For an exercise program to be effective, it must elicit a variety of strains above those encountered in daily movement without overloads that are unsafe. For example, exercises that involve bending forward from the waist could endanger clients diagnosed with osteoporosis of the spine.
A clinical study, the Bone Exercise Strength Training Study (BEST), conducted by researchers at the University of Arizona, between 1995 and 2001, showed that weight bearing and resistance exercises, along with calcium supplementation, significantly improved bone mineral density at those sites most frequently associated with osteoporotic fractures in post-menopausal women. The study led to the development of the BEST Exercise Program for Osteoporosis Prevention.